got my set from the guy called chris who runs that section, was very helpful, got the offset/width I wanted for a good price delivered. Have the alloys on the car now for 6000 miles with no trouble.
For the sake of a few hundred pounds I'd go OEM if I were you, you can pick up a set from £700+ if you don't mind having a refurb, I paid a little less and did the refurb myself, i know a member on here got a set for around the same money that didn't need a refurb, so they are out there if you're patient, there is a set on eBay for £999, they say genuine but I don't think they are, be careful and use the guide on here to differentiate, good luck
If you search the forum for " how to identify genuine CSL's" thread it was invaluable to me, the first set I went to see were described as OEM, the seller didn't know, they bought them as genuine, but they weren't .